Workers' load and job-related stress after a reform and work system change in a hospital kitchen in Japan.

OBJECTIVES: Many kitchen work environments are considered to be severe; however, when kitchens are reformed or work systems are changed, the question of how this influences kitchen workers and environments arises. The purpose of this study is to examine whether there was a change in workload and job-related stress for workers after a workplace environment and work system change in a hospital kitchen. METHODS: The study design is a pre-post comparison of a case, performed in 2006 and 2008. The air temperature and humidity in the workplace were measured. Regarding workload, work hours, fluid loss, heart rate, and amount of activity [metabolic equivalents of task (METs)] of 7 and 8 male subjects pre- and post-reform, respectively, were measured. Job-related stress was assessed using a self-reporting anonymous questionnaire for 53 and 45 workers pre- and post-system change, respectively. RESULTS: After the reform and work system change, the kitchen space had increased and air-conditioners had been installed. The workplace environment changes included the introduction of temperature-controlled wagons whose operators were limited to male workers. The kitchen air temperature decreased, so fluid loss in the subjects decreased significantly. However, heart rate and METs in the subjects increased significantly. As for job-related stress, although workplace environment scores improved, male workers' total job stress score increased. CONCLUSIONS: These results suggest that not only the workplace environment but also the work system influenced the workload and job stress on workers.

Identifying factors that inhibit or facilitate on-site implementation of chemical risk assessment at small and medium-sized companies.

The introduction and implementation of chemical risk assessment is difficult, especially at small and medium-sized manufacturing and construction companies. This study aimed to identify the factors that inhibit or facilitate such assessment. Twelve individuals in charge of risk assessment at one medium-sized client company and eight small and medium-sized contract companies and responsible for innovation in the manufacturing and construction industries were interviewed. The interview transcripts were analyzed via text mining using KH Corder ver. 3 and a co-occurrence network was used to identify the keywords' connections and each factor in consideration of the interviews. Six factors inhibited or facilitated risk assessment: (1) education on hazardous work in the workplace, (2) improvement suggestions and reduction measures from client and staff, (3) cooperation between employees and contractors in the workplace, (4) thoroughly explanation of SDS content for better understanding, (5) risk awareness based on accident examples, and (6) difficulties imagining the hazards of chemical substances. Factors (1), (2), (3), and (5) were positive, facilitating factors; (4) and (6) were negative, inhibiting factors. This study highlights that it is necessary to educate workers about chemical substance risks using safety data sheets and accident examples in chemical risk assessment.

Prevalence of self-reported finger deformations and occupational risk factors among professional cooks: a cross-sectional study.

BACKGROUND: Previous studies have pointed out that the school lunch workers in Japan are suffering from work-related disorders including finger deformations. The purpose of this study was to investigate the prevalence of self-reported finger deformations and the association with job-related risk factors. METHODS: A cross-sectional questionnaire study of 5,719 subjects (response rate: 81%, 982 men and 4,737 women) was undertaken during September 2003 to February 2004. RESULTS: Finger deformations were found among 11.7% of the men and 35.6% of the women studied, with significant differences among sex, age and sex-age groups. For both men and women the pattern of finger deformations across the hand was similar for the right and the left hand. For women, the deformations were found in about 10% of the distal interphalangeal joints of all fingers. Based on multiple logistic regression analyses, the factors female sex, age, the number of cooked lunches per cook and cooking activities were independently associated with the prevalence of finger deformations. High prevalence odds ratios were found for those frequently carrying or using tools by hands such as delivering containers, distributing meals, preparing dishes, washing equipment, cutting and stirring foods. CONCLUSIONS: Among the school lunch workers studied, women had a higher prevalence of finger deformations on all joints of both hands. Various cooking tasks were associated with the prevalence of finger deformations. The results suggest that improvements in working conditions are important for preventing work-related disorders such as finger deformations.

[The effect of a semi-dry processing system on the thermal environment in school lunch kitchens].

The thermal conditions of elementary school lunch kitchens applying dry, semi-dry and wet processing systems were studied. We focused especially on the improvement of the microclimate of a kitchen applying a semi-dry processing system. The survey was conducted in two individual school kitchens with a semi-dry system (School A) and a dry system (School B). Air temperature, relative humidity and air velocity were measured at 8 to 13 points every hour in September, 2006 in School A and B, and in February, 2007 in School A. Since a similar survey had been conducted in the kitchen of School A when the cooking work had been going on in a wet manner in February and September, 1990, it was possible to compare the measurement data from this study and those from the former study. The difference between indoor and outdoor absolute humidity was used as an index of the humidification of the cooking work in the kitchen. By comparing the microclimate of School A in 2006/2007 and 1990, it was found that the differences in absolute humidity in the semi-dry systems were significantly lower than those in the wet systems during the working hours in the summer mornings and in the winter afternoons, and the floor was maintained in drier conditions. It is suggested that a reduction of humidity in the kitchen by introducing a semi-dry or a dry processing system would contribute to not only an improvement in the working environment, such as the reduction of foot chill in winter and food sanitation, but also to a reduction in the workloads of cooking workers.

[Effects of aircraft noise on preschool children's misbehaviours: results of research around the Kadena and Futenma airfields in Okinawa].

OBJECTIVES: To investigate the association between aircraft noise exposure as expressed by Weighted Equivalent Continuous Perceived Noise Level (WECPNL) and preschool children's misbehaviours around the Kadena and Futenma airfields in Okinawa. METHODS: A questionnaire survey on children's misbehaviour was conducted in nursery schools and kindergartens around the Kadena and Futenma airfields. The children living around the Kadena airfield were divided into four groups according to WECPNL at their residences and those around the Futenma airfield into three groups according to WECPNL. The subjects were 1,888 male and female preschool children, 3 to 6 years of age, whose parents, caregivers, and teachers answered the questions. The answers used for the analysis were limited to those of respondents fulfilling the following conditions: parents living with their children, fathers with a daytime job, and mothers with a daytime job or no job. Thus, the number of valid answers was 1,213. The responses were analysed using logistic regression models taking the number of misbehaviours related to the items of Biological Function, Social Standard, Physical Constitution, Movement Habit, or Character as the dependent variables, and WECPNL, age, sex, size of family, birth order, mother's age at birth, mother's job, caregiver's career, and category of subject as the independent variables. RESULTS: A significant dose-response relationship was found between the odds ratio and WECPNL for the outcomes of Physical Constitution around the Kadena and Futenma airfields. CONCLUSIONS: It would be reasonable to conclude that the aircraft noise exposure is a factor that increases the number of preschool children's misbehaviours.

Prevalence and risk factors for low back pain among professional cooks working in school lunch services.

BACKGROUND: The prevalence of self-reported low back pain among professional cooks was estimated to examine the effects of daily life conditions, job-related factors, and psychological factors on this disorder. METHODS: Data was collected using a mailed self-administered questionnaire. RESULTS: Of 7100 cooks, 5835 (82%) replied to the questionnaire, including 1010 men and 4825 women. The mean age was 41.4 for men and 47.5 for women. The prevalence of low back pain during a 1-month period was 72.2% among men and 74.7% among women, with no significant differences between groups. By logistic regression analyses, factors significantly associated with the prevalence of low back pain in 1 month were female gender (prevalence ratio [PR] 1.32; 95% CI, 1.03-1.68), current smoking (PR 1.57; 95% CI, 1.24-1.98), and past smoking (PR 1.35; 95% CI, 1.01-1.79). As for job-related factors, the number of cooked lunches per person (PR 1.28; 95% CI, 1.05-1.56), breaks in the morning session (PR 1.33; 95% CI, 1.13-1.56), kitchen environment (PR 1.09; 95%, CI, 1.03-1.15), and height of cooking equipment (PR 1.13; 95% CI, 1.08-1.19) were associated with the prevalence of low back pain. As for psychological factors, job satisfaction (PR 1.22; 95% CI, 1.03-1.45), stress at work (PR 1.68; 95% CI, 1.42-1.99), financial constraints (PR 1.23; 95% CI, 1.03-1.47), health-related stress (PR 1.31; 95% CI, 1.08-1.59) and worries about the future (PR 1.24; 95% CI, 1.01-1.52) were similarly associated. CONCLUSION: Daily life conditions, job-related factors, and psychological factors are associated with the occurrence of low back pain. It is important to take comprehensive preventive measures to address a range of work and life conditions that can be improved to decrease the incidence of low back pain for professional cooks.

Development of interactive workplace improvement programs in collaboration with trade associations of small-scale industries.

Serial participatory action programs for reducing occupational safety and health risks were undertaken to know the types of support suited for small-scale industries. Working groups were formed with workplace people and occupational safety and health experts. It was agreed to develop an action-oriented strategy focusing on improving both work environment and productivity by making low-cost improvements through group work. Many workplace improvements achieved by participating enterprises and the group work procedures taken were analyzed. As supporting tools for effectively implementing the workplace improvement action programs, we developed action checklists according to industry and workplace implementation guides. Collections of local good examples also served as part of these support tools. These experiences show that keys to the sustainable action in small-scale industries are: (1) mobilization of the industry-wise network by trade associations, (2) an output-oriented strategy based on interactive group work and (3) the effective use of support tools such as low-cost action checklists and group work methods.

Development of multi-dimensional action checklist for promoting new approaches in participatory occupational safety and health in small and medium-sized enterprises.

To meet diversified health needs in workplaces, especially in developed countries, occupational safety and health (OSH) activities should be extended. The objective of this study is to develop a new multi-dimensional action checklist that can support employers and workers in understanding a wide range of OSH activities and to promote participation in OSH in small and medium-sized enterprises (SMEs). The general structure of and specific items in the new action checklist were discussed in a focus group meeting with OSH specialists based upon the results of a literature review and our previous interviews with company employers and workers. To assure practicality and validity, several sessions were held to elicit the opinions of company members and, as a result, modifications were made. The new multi-dimensional action checklist was finally formulated consisting of 6 core areas, 9 technical areas, and 61 essential items. Each item was linked to a suitable section in the information guidebook that we developed concomitantly with the action checklist. Combined usage of the action checklist with the information guidebook would provide easily comprehended information and practical support. Intervention studies using this newly developed action checklist will clarify the effectiveness of the new approach to OSH in SMEs.

[Status of noise in small-scale factories having press machines and hearing loss in workers].

A study on noise and hearing loss was conducted in 36 small-scale factories where press machinery is actively used. Noise levels in working environments were measured in 34 factories. Of those measured, two (6%), eight (24%) and 24 (71%) factories were classified into control classes I, II and III, respectively, according to guidelines established for the prevention of noise-related disorders. Furthermore, personal exposure levels to noise were measured for 23 workers. Twenty-one (91%) of those workers measured were exposed to 85 dB(A) or higher, (the occupational exposure limit for an 8-hour exposure period). Maximum exposure levels were found to be at 102 dB (A). Hearing tests were then conducted on 97 male workers at those 36 factory sites. Twenty (21%), 30 (31%) and 10 (10%) of the workers measured were classified into a "precursory symptom group", a "slight hearing loss group" and a "medium to serious hearing loss group", respectively, based on the aforementioned guidelines. It was found that as workers' ages increased, the percentage of workers having some degree of hearing loss increased. Specifically, it was found that there was some level of hearing loss for 93% of those studied aged in their 50's, and up to 100% in those aged in their 60's.

Burn and cut injuries related to job stress among kitchen workers in Japan.

To clarify the correlation between kitchen work-related burns and cuts and job stress, a self-administered questionnaire survey was conducted involving 991 kitchen workers among 126 kitchen facilities. The demographics, condition of burns and cuts, job stress with the Brief Job Stress Questionnaire (BJSQ), health condition, and work-related and environmental factors were surveyed. Multiple logistic regression models and trend tests were used according to quartiles (Q1, Q2, Q3, and Q4) of each sub-scale BJSQ. After adjustment for potential confounding variables, burns/cuts were associated with a higher score category (Q4) of job demands (OR: 2.56, 95% CI: 1.10-6.02/OR: 2.72, 95% CI: 1.30-5.69), psychological stress (OR: 4.49, 95% CI: 2.05-9.81/OR: 3.52, 95% CI: 1.84-6.72), and physical stress (OR: 2.41, 95% CI: 1.20-4.98/OR 2.16, 95% CI: 1.16-4.01). The ORs of the burn/cut injures increased from Q1 to Q4 with job demands (p for trend = 0.045/0.003), psychological stress (p for trend<0.001/0.001), and physical stress (p for trend = 0.006/0.005), respectively. These findings suggest that kitchen work-related burns and cuts are more likely to be correlated with job stress, and the higher the job stress score, the higher the frequency of burns and cuts among kitchen workers.

Risk factors for frequent work-related burn and cut injuries and low back pain among commercial kitchen workers in Japan.

This study investigated risk factors for frequent work-related burn and cut injuries and low back pain (LBP) among kitchen workers including personal, work-related and environmental factors. Subjects were 991 kitchen workers in 103 schools, 17 hospitals and nursing homes, and 6 restaurants in central Japan. A cross-sectional survey was carried out using a structured self-administered questionnaire. Logistic regression models were used to examine associations between frequent injuries/LBP and risk factors. The effective response rate was 75.1% (n=744), the mean age was 40.7 (SD 11.7) and 77.2% were female. Burn injury was associated with a smaller kitchen (OR 1.94; 95%CI, 1.13-3.33), and gas kitchens rather than electric kitchens (OR 2.30; 95%CI, 1.17-4.52). LBP was associated with female gender (OR 2.46; 95%CI, 1.37-4.43), high body height (>160 cm) (OR 2.03; 95%CI, 1.22-3.36), and large number of meals produced per person (≥ 150 meals) (OR 1.83; 95%CI, 1.12-3.00). The results of this study suggest that securing adequate work space and introducing electric kitchen systems may reduce the risk to kitchen workers, as well as the importance of adequate height of cooking equipment and selecting an appropriate volume of meals to produce per person to prevent LBP in kitchen workers.

The effects of work environments on thermal strain on workers in commercial kitchens.

The purpose of this study was to clarify the effect of working environments of different kinds of commercial kitchens on the thermal strain of kitchen workers. This study design was cross-sectional study, and data collection was performed during busy time in commercial kitchen from August to September 2006. The research subjects were 8 institutions, involving 7 cookers, and 16 men. Measured environmental variables were air temperature, radiant heat index, wet bulb globe thermometer index (WBGT) in front of the cookers, ambient temperature, and estimated ambient WBGT around the workers. The thermal strain on workers was evaluated by fluid loss, body temperatures, heart rate and amount of physical activity (METs). All average estimated ambient WBGTs in front of cookers were less than 27.5℃. The average heart rate was 107 ± 10 bpm, and average METs was 2.0 ± 0.6. The peak values of upper arm skin temperature and auditory canal temperature were less than 37.5℃. The work environments were affected by the kitchen spaces, cooling devices, heating methods, and heat sources. Even in the midsummer, if environmental temperatures were controlled adequately, estimated ambient WBGTs around workers were below the occupational exposure limit. Work environments and thermal strain on workers in commercial kitchen were not severe.

Evaluation of subjective thermal strain in different kitchen working environments using subjective judgment scales.

To elucidate the subjective thermal strain of workers in kitchen working environments, we performed a cross-sectional study involving 991 workers in 126 kitchen facilities in Japan, using a self-reporting questionnaire survey and subjective judgment scales (SJS). The ambient temperature, mean radiant temperature (MRT), and wet-bulb globe temperature (WBGT) index were measured in 10 kitchen facilities of the 126 kitchens. The association of SJS with the types of kitchen was estimated by multiple logistic regression models. Of the 991 kitchen workers, 809 (81%) responded to the questionnaire survey. Compared with the electric kitchens, the proportion of workers who perceived the room temperature as hot to very hot was significantly higher, and the ambient temperature, MRT, and WBGT were significantly higher in the gas kitchens. Compared with the electric kitchens, workers in gas kitchens had a more than fivefold (males) and tenfold (females) higher SJS adjusted for confounding factors (male odds ratio (OR), 5.13; 95% confidence interval (CI), 1.65-15.9; and female OR, 10.9; 95%CI, 3.89-30.5). Although SJS was affected by some confounding factors, our results suggest that workers in gas kitchens might be exposed to a higher heat strains than those in electric kitchens.

[Qualitative evaluation of employer requirements associated with occupational health and safety as good practice in small-scale enterprises].

The purpose of this study was to identify what motivates employers to promote good occupational health and safety practices in small-scale enterprises. Previous studies have shown that small-scale enterprises generally pay insufficient attention to issues of occupational health and safety. These findings were mainly derived from questionnaire based surveys. Nevertheless, some small-scale enterprises in which employers exercise good leadership do take a progressive approach to occupational health and safety. Although good practices can be identified in small-scale enterprises, it remains unclear what motivates employers in small-scale enterprises to actively implement occupational health and safety practices. We speculated that identifying employer motivations in promoting occupational health would help to spread good practices among small-scale enterprises. Using a qualitative approach based on the KJ methods, we interviewed ten employers who actively promote occupational health and safety in the workplace. The employers were asked to discuss their views of occupational health and safety in their own words. A semi-structured interview format was used, and transcripts were made of the interviews. Each transcript was independently coded by two or more researchers. These transcripts and codes were integrated and then the research group members discussed the heading titles and structural relationships between them according to the KJ method. Qualitative analysis revealed that all the employers expressed a strong interest in a "good company" and "good management". They emphasized four elements of "good management", namely "securing human resources", "trust of business partners", "social responsibility" and "employer's health condition itself", and considered that addressing occupational health and safety was essential to the achievement of these four elements. Consistent with previous findings, the results showed that implementation of occupational health and safety activities depended on "cost", "human resources", "time to perform", and "advisory organization". These results suggest that employer awareness of the relationship between good management and occupational health is essential to the implementation of occupational health and safety practices in small-scale enterprises.

Effects of heating appliances with different energy efficiencies on associations among work environments, physiological responses, and subjective evaluation of workload.

To clarify the association between heat stress, physiological responses and subjective workload evaluations in kitchens using an induction heating stove (IH stove) or gas stove. The study design was an experimental trial involving 12 young men. The trial measured ambient dry-bulb temperature, globe temperature, wet-bulb globe temperature (WBGT) and relative humidity; the subjects' weight, heart rate, blood pressure, oxygen uptake, amount of activity, body temperature, subjective awareness of heat and workload before and after mock cooking for 30 min. The IH stove insignificantly increased heat indicators in the work environment and workers showed lower oxygen uptake, skin temperature, subjective awareness of heat and workload after heat exposure. Both physiological load and subjective awareness of heat and workload were slight in kitchens using the IH stove, which provided a better work environment.